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1.
酞菁钴/铁纳米填充母粒组成的磁流变液性能   总被引:3,自引:0,他引:3  
采用有机/无机原位(insitu)复合方法制备得出酞菁钴/铁纳米填充母粒,与甲基硅油组成磁流变液(MRS)。MRS的附加动态剪切应力(Δτ)与分散介质浓度、外加磁场强度呈正比例关系;剪切速率对Δτ的影响表明磁致流变为链状结构特征;Δτ对温度不敏感;MRS对外加磁场有可逆的开/关变化特征,无记忆效应,磁流变响应时间小于0.1s。  相似文献   

2.
酞菁钴/SnO2纳米复合材料的原位合成及可见光光催化   总被引:3,自引:0,他引:3  
酞菁钴/SnO2纳米复合材料的原位合成及可见光光催化;SnO2;酞菁钴;纳米复合材料;原位合成;光催化  相似文献   

3.
新型有机-无机纳米复合粒子的制备及其固定化漆酶研究   总被引:2,自引:0,他引:2  
制备了四氨基酞菁钴(CoTAPc)-Fe3O4纳米复合粒子, 用红外光谱(IR)、X射线衍射(XRD)、X射线能谱(EDS)、场发射扫描电镜(FEG-SEM)及振动样品磁强计等对其进行了表征. 结果表明, 形成了CoTAPc包覆在Fe3O4纳米粒子表面的纳米复合粒子. 粒子呈现不规则球形, 平均粒径为70 nm, 矫顽力为316.4 A/m, 接近超顺磁性. 以此纳米复合粒子作为载体, 通过交联法固定漆酶, 固定化酶最适反应温度为45 ℃, 最适pH为3; 固定化酶比游离酶具有更好的热稳定性、贮存稳定性及操作稳定性, 且易于分离.  相似文献   

4.
以四磺酸铝氯酞菁1为原料,采用氨基转化法,经磺酰氯化和Hinsberg磺酰胺化反应合成四磺酰铝氯酞菁2和四(6-氨基己酸磺酰基)铝氯酞菁3,产物结构经元素分析,IR,1HNMR和MS-ESI表征。3在磷酸盐缓冲溶液中与两亲嵌段共聚物聚乙二醇-聚-L-赖氨酸(PEG-b-PLL)通过静电自组装,形成负载3的聚合物纳米粒子3/m。原子力显微镜(AFM)和透射电子显微镜(TEM)表明3/m具有球形核壳结构,直径约为10~20 nm。紫外-可见吸收光谱和荧光光谱法研究了3/m的光物理性质。通过对不同孵育时间的人脐带血内皮细胞(HUVEC)摄取药代动力学测定3/m细胞摄取率和MTT法评价3/m的离体光动力活性,相对自由酞菁3,3/m的细胞摄取率大大提高,且提前1 h达到最高浓度,而且细胞抑制率明显增大,约为3的2倍。  相似文献   

5.
本文报道了一种方便地构建铂/酞菁/碳纳米管(Pt/Pc/CNTs)复合纳米催化剂的新方法:先通过简单的超声处理将酞菁分子(Pc)修饰至碳纳米管表面,随后采用乙二醇还原法将铂纳米粒子固载到酞菁修饰的碳纳米管表面,形成Pt/Pc/CNTs复合纳米催化剂。X射线衍射(XRD)和透射电镜(TEM)结果表明金属铂纳米颗粒均匀地分散在碳纳米管表面,尺寸约5 nm。采用UV-Vis、FTIR和Raman等手段研究了这种复合纳米催化剂的构建过程,结果表明酞菁分子与碳纳米管之间存在较强的π-π相互作用,使其能牢固地吸附于碳  相似文献   

6.
FeOOH明胶复合纳米粒子的制备与表征   总被引:1,自引:0,他引:1  
采用两步法制备具有弱磁性的FeOOH纳米粒子和FeOOH明胶复合纳米粒子.透射电镜、扫描电镜、红外光谱、X射线衍射和磁滞回线等测量结果表明:在一定FeCl3/Fe2(SO4)3/H2O摩尔比条件下,加入十二烷基苯磺酸钠(ABS)溶液,可制备粒径为30~150nm弱磁性FeOOH纳米粒子,其磁性可达6.5×10-6emu/g.弱磁性FeOOH纳米粒子可被明胶包裹.随着FeCl3/Fe2(SO4)3摩尔比减小或明胶浓度增加,纳米球粒径增大,磁性降低.随着固化时间增加,FeOOH明胶复合纳米粒子的粒径先增大后减小.  相似文献   

7.
同轴静电纺丝法在纳米中空TiO2纤维中填充Ag的应用   总被引:2,自引:0,他引:2  
以聚乙烯吡咯烷酮(PVP)溶胶/钛酸四正丁酯和PVP溶胶/银颗粒为前驱体,以共轴静电纺丝法制备了银填充的TiO2中空纳米纤维.将双组分纤维在200℃下热处理去除乙醇与表面吸附水后,继而在空气气氛中焙烧至600℃,可以得到在内表面上沉积银颗粒的TiO2纳米管,银颗粒的直径为5-40nm,TiO2纳米管的外径150-300nm,管臂厚10-20nm.用红外吸收光谱(IR)、X射线衍射(XRD)、扫描电子显微镜(SEM)、透射电子显微镜(TEM)等测试手段对超细纤维进行了表征.中空纤维的直径和管壁可以通过改变电纺参数来调节.与Ag-TiO2纳米纤维、TiO2纳米中空纤维、TiO2纳米纤维及TiO2纳米粉体相比较,Ag颗粒填充的TiO2纳米中空纤维在光分解亚甲基蓝上表现出了更好的光催化性能.  相似文献   

8.
同轴静电纺丝法在纳米中空TiO2纤维中填充Ag的应用   总被引:1,自引:0,他引:1  
以聚乙烯吡咯烷酮(PVP)溶胶/钛酸四正丁酯和PVP溶胶/银颗粒为前驱体, 以共轴静电纺丝法制备了银填充的TiO2中空纳米纤维. 将双组分纤维在200 ℃下热处理去除乙醇与表面吸附水后, 继而在空气气氛中焙烧至600 ℃, 可以得到在内表面上沉积银颗粒的TiO2纳米管, 银颗粒的直径为5-40 nm, TiO2纳米管的外径150-300 nm, 管臂厚10-20 nm. 用红外吸收光谱(IR)、X射线衍射(XRD)、扫描电子显微镜(SEM)、透射电子显微镜(TEM)等测试手段对超细纤维进行了表征. 中空纤维的直径和管壁可以通过改变电纺参数来调节. 与Ag-TiO2纳米纤维、TiO2纳米中空纤维、TiO2纳米纤维及TiO2纳米粉体相比较, Ag颗粒填充的TiO2纳米中空纤维在光分解亚甲基蓝上表现出了更好的光催化性能.  相似文献   

9.
用循环伏安电沉积法在玻碳基底上制备纳米结构钴薄膜, 扫描电子显微镜研究结果表明, 纳米结构钴薄膜主要由平均粒径为150 nm的钴粒子组成, 同时还有为数不多的粒径在400~500 nm的钴粒子. 以CO为探针分子, 结合原位傅里叶变换红外反射光谱研究结果, 发现所制备的纳米结构钴薄膜具有异常红外效应. 吸附态CO发生异常红外吸收, 谱峰增强了26.2倍, 测得线型吸附态COL的Stark系数为77.5 cm-1·V-1.  相似文献   

10.
通过软复型和水热法制备出一种由有机材料和ZnO纳米棒组成的微纳米结构复合表面,这种表面的微米结构是周期为300μm、高度为70μm的锯齿状结构,ZnO纳米线的直径为300~500 nm,长度为2~3μm.这种有机材料和ZnO纳米线复合成的表面经过全氟硅烷修饰后,具有良好的低黏滞特性和低温超疏水性(约为150°)以及较长的结冰延时性(6000~7630 s),实验结果对设计表面低温疏水/疏冰材料具有参考价值.  相似文献   

11.
非那雄胺能抑制5α-还原酶的活性,明显降低二氢睾酮水平,是一种治疗良性前列腺增生的有效药品。该合成工艺以甾烯酮酸为原料,将其与氯化亚砜反应,无须分离即与叔丁胺反应得17β-酰胺化合物,再氧化开环,环合,氢化,脱氢合成了非那雄胺。经元素分析、IR、1HNMR、13CNMR、MS分析表征了其结构。该法无须使用昂贵的2,2-二吡啶二硫化物和剧毒药品苯亚硒酸酐,且以乙酸铵代替氨气,降低了对设备的要求和腐蚀,更适用于工业生产。  相似文献   

12.
The spectral-polarization characteristics of absorption and phosphorescence of molecules of the initial form of nitro-substituted indolinospirobenzothiopyran were studied in oriented polyethylene films and in solutions with different polarity. An oscillator model of the electron transitions responsible for the formation of absorption and luminescence spectra was suggested. It was established that the principal differences in the spectral and photophysical properties of the compound studied and its oxygen-containing analog are associated with the fact that the electronegativity of the S atom is lower than that of the O atom. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1143–1146, June, 1997.  相似文献   

13.
翟宗玺  刘树深  夏树屏 《化学学报》1990,48(10):946-950
用氧化镁氯化镁水溶液制备了8水合氯氧化镁[nMg(OH)2·MgCl2·8H2O], 并测定了其在盐酸中的溶解热, 实验结果表明, 氯氧化镁溶解热与n值呈线性关系, 根据溶解热求出5Mg(OH)2·MgCl2·8H2O和3Mg(OH)2·MgCl2·8H2O的生成热分别为-7727.1和5888.1kJ·mol^1^-。  相似文献   

14.
Two vanilloids, (5E)-8-(4-hydroxy-3-methoxyphenyl)oct-5-en-4-one (1) and 4-[3-hydroxydecyl]-2-methoxyphenol (2), isolated from the dried seeds of Grains of Paradise (Aframomum melegueta), were synthesized; the latter compound was made as the S-enantiomer and the material derived from the seeds was found to be a 1:1.7 mixture of the R and S isomers. The synthetic route used should allow the preparation of analogs having extended alkyl chains and consequently different lipophilicity, and 3, a homolog of 2, was also prepared.  相似文献   

15.
Cotton cellulose was swollen in a sodium hydroxide solution and carboxymethylated by a two-bath method for different periods of time for each process. The kinetics of acid hydrolysis and the crystallinity of the swollen and carboxymethylated samples were measured. The proportion of broken bonds, rate constants for hydrolysis, and permeability of cellulose to hydrolyzing agents were calculated. The susceptibility of glycosidic linkages to acid hydrolysis was improved by carboxymethylation more than by swelling in alkali. The increased accessibility of carboxymethylcellulose to acid was regarded as a consequence of increased intra-and intercrystalline swelling and of the glycosidic bonds' weakness caused by the electron-attracting carboxymethyl group on the C-6 position.  相似文献   

16.
Cyclopropyl derivative of 2,6-di-tert-butylphenol is synthesized as a probe to investigate the mechanism of base-catalyzed autooxidation of phenol derivatives. Our study indicates that one electron reduction of molecular oxygen from phenolate gives phenoxyl radical 3, a key intermediate of autooxidation. The coupling of phenoxyl radical and superoxide radical gives peroxylate anion 4 and produces the final epoxy alcohol adduct 6.  相似文献   

17.
The aim of the presented work was the investigation of thermal oxidation of ilmenite in static air atmosphere. The investigations were carried out by use of a derivatograph (MOM, Hungary). The changes of crystallographic structure of investigated samples were identified by X-ray diffractometry on Philips PW-1710 diffractometer. In temperature above 500°C appears structure of hematite Fe2O3. On the basis of the thermogravimetric measurements, the contracting area and contracting volume models were found as the best fitting experimental data. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

18.
Main hydration products of two cement pastes, i.e. CSH-gel, portlandite (P) (and specific surface S) were studied by static heating, and by SEM, TEM and XRD, as a function of cement strength (C-33 and C-43) hydration time (th) and subsequent hydration in water vapour.Total change in mass on hydration and air drying, Mo, increased with strength of cement paste and with hydration time. Content of water escaping at 110 to 220°C, defined as water bound with low energy, mainly interlayer and hydrate water, was independent on cement strength but its content increased with (th). Content of chemically bound (zeolitic) water in CSH-gel, escaping at 220-400°C, was slightly dependent on strength and increased with (th). It was possibly derived from the dehydroxylation of CSH-gel and AFm phase. Portlandite water, escaping at 400-500°C, was independent on cement strength and was higher on longer hydration. Large P crystals were formed in the weaker cement paste C-33. Smaller crystals were formed in C-43 but they increased with (th). Carbonate formated on contact with air (calcite, vaterite and aragonite), decomposed in cement at 600-700oC. It was high in pastes C-33(1 month) and C-43(1 month), i.e. 5.7 and 3.3%, respectively; it was less than 1% after 6 hydration months (low sensitivity to carbonation) in agreement with the XRD study showing carbonates in the air dry paste (1month), and its absence on prolonged hydration (6 months) and on acetone treatment. Water vapour treatment of (6 months) pastes or wetting-drying increased this sensitivity.Nanosized P-crystals, detected by TEM, could contribute to the cement strength; carbonate was observed on the rims of gel clusters.This revised version was published online in November 2005 with corrections to the Cover Date.  相似文献   

19.

The heats of detonation of 20 simple high explosives and explosive mixtures were determined by means of an adiabatic detonation calorimeter designed by the authors. The results indicated that the performance of the instrument was reliable and the experimental data were very accurate. For explosive mixtures, there was a linear accumulative relationship between the heats of detonation of the explosive mixture and its components. Accordingly, the heats of detonation of explosive mixtures could be calculated directly from the heats of detonation of simple explosives and the characteristic heats of other components. The experiments showed that the gold or brass shell of the cylindrical charge could be substituted by a thick-walled porcelain shell, which had the advantage of cheapness.

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20.
潘素娟  全灿  周俊波 《化学通报》2014,77(12):1165-1170
测量不确定度是表征合理地赋予被测量之值的分散性的参数。本文针对化学计量不确定度评定基础模型仅适用于线性模型、概率分布为正态分布或缩放位移t分布等局限,介绍了近年来不确定度评定的研究热点:蒙特卡罗方法(Monte Carlo Method,MCM),不确定度评定的来源、评定概念、评估方法及其发展过程,扩大了测量不确定度评定与表示的适用范围。  相似文献   

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